ferraris



Jan. 3l, 1956 J. T. FERRARIS CONTROL FOR AUTOMATIC VACUUM CLEANERS I5Sheets-Sheet 1 Filed Jan. 29, 1954 .E QR. um l@ t Nw wh f NQ NQ Q f/ wwwNQ SQ QE Q mw ooo o mm1- o o O O o o o o .N5 ,h o o @lo SQ N5 Q |ii. NNww Nw .o O O Il lll. uhrmwfd.. 9| up ma l/ATTORN EY Jan 31, 1956 J. T.FERRARIS CONTROL FOR AUTOMATIC VACUUM CLEANERS Filed Jan. 29, 1954 3Sheets-Sheet 2 INVEN OR y Y /MATTORNEY Jan- 31, 1956 J. T. FERRARISCONTROL FOR AUTOMATIC VACUUM CLEANERS 5 Sheets-Sheet 3 Filed Jan. 29,1954 y R m INVENTOR BY ZW/,4M

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United States Patent O CONTROL FOR AUTOMATIC VACUUM CLEANERS John T.Ferraris,`Stamford, Conn., assigner to Electrolux Corporation, OldGreenwich, Coun., a corporation of Delaware My` invention relates tovacuum cleaners and more particularly to vacuum cleaners of theautomatic type wherein the operation of the cleaner is controlled inaccordance with variations in air pressure occurring within the cleanerduring use. i

A preferred arrangement involves a pressure differential diaphragm orthe like which is responsive to the pressure drop yofthe air passinglthrough the dust bag or other dust separating member for actuating avalve controlling the application of pressure or vacuum to a powerdiaphragm. Such device is so designed and constructed that it` willactuate the valve upon the attainment of a predetermined pressure drop.The resulting actuation of the power diaphragm may cause merely theoperation of a visibleor audible signal, orit maj/.include stopping themotor of the cleaner, opening the front cover and ejecting the dustcontainer, or any one orfmore of these operations.

Another object of my invention is to assure that once the valve operatedby the pressure diierential diaphragm has opened, the power diaphragmwill be rapidly and fully-actuated, even though this valve subsequentlyshould close. I` accomplish this by providing a second valve which isopened bythe initial displacement of the power diaphragm so as todirectly apply pressureor vacuum thereto independently of `the' lirstvalve.

`Further objects and advantages of my invention will bel apparent fromthe following description when considered. in connection with theaccompanying drawings which form a part of the speciiication and. ofwhich:

Fig. 1 is a side view, chiefly in cross-section, showing a vacuumcleaner embodying my invention;

Fig. 2 is a top view on an enlarged scale of a: control unit and frontcover of thevacuum cleaner shown in Fi 1;

t(lgig. 3 is a cross-sectional view on an enlarged scale taken on theline 3-3 of Fig. 2; i Fig. 4 is a cross-sectional view on an enlargedscale taken on the line 4--4 of Fig. 2; and

Fig. 5 is a cross-sectional view taken on the line 5- Referring to thedrawings, and more particularly to Fig. 1, reference characterltldesignates an airtight elongated body mounted on a pair of runners 12which movably support the body in a substantially horizontal position ona surface, such as a iloor. Disposed in the righthand portion of thebody, as viewed in Fig. 1, is a motorfan unit comprising a fan 14 drivenby an electric motor 16,` the motor-fan unit being mounted within thebody by means of an airtight partition or bulkhead 18. The fan isprovided with an inlet opening which communi- Cates with the spacewithin the body to the left of the bulkhead. Within this space there isdisposed an inner body 22 formed with a large number of apertures 24 soas toprovide substantially unobstructed communication between theinterior of the inner body and the inlet 20. IThe left end of therinnerbody is open and is secured to a ring 26 which is in turn secured-in theopen end of the outer body 10. i

Depending from the lower part of ring 26 is a wall portion 28 whichforms the front end and part of the bottom of a .control chamber 30. Theenclosure of the chamber 30 is completed by a removablestamping or thelike 31. Extending forwardly from the wall 28 is a pair c-t projections32 to which is hinged a cover 34 by means of a pin 36. A coil spring 38surrounds this pin and urges the cover to the open position shown inFig. 2. As seen in Fig. 2, the left-hand portion of the cover, which isthe upper portion when the cover isclosed, is formed with a cut-outportion 40 within which `is pivotally mounted a hose connector member 42by means of pins 44. A link 48 is pivotally connected to the hoseconnector and 4to one of the projections 32, this link together with thecover 34 constituting a parallel motion linkage for causing the hoseconnector 42 to move parallel to itself as the cover is opened andclosed.

The hose connector is formed with an` opening 50 extending therethrough,the outer end of which is formed as a portion of a separable couplingwhereby a suction hose may be connected theerto. The inner end of theopening communicates with an inlet conduit 52 which is surrounded by aflexible gasket 54.

Removably disposed `within the inner body 22 is a dust separating member56 made of porous material, such as paper, which is secured at one endto a stiif cardboard disc 58. This discis formed with a centrallylocated aperture adapted to ,receive the inlet conduit 52 when the coveris in the closed position shown in Fig.'1, the gasket 54 bearing againstthe disc and holding the edges thereof in position against a gasket 60carried by the ring 26, thus closing this end of the body 10.

Secured below the airtight body 10 by means of a plurality of bolts` 62`is a control unit comprising a differential pressure diaphragm housing64 and a power diaphragm housing 66. Secured within the housing 64 is adifferential pressure diaphragm 68 which divides the housing into anupper high vacuum chamber 70. and into a lower low vacuum chamber 72.Chamber 70 is connected to the interior of body 10 throughan opening 74Vin the housing which communicates with an aperture Y76 in the body. Agasket 77 is carried by housing 64 and bears against the bottom of body10 around the opening 76 to prevent leakage. This chamber 70`may also beconnected toatmosphere through an adjustable valve 78. This valveincludes a screw threaded valve member 80, the end of which may beadjustably positioned with respect to a passage 82 leading to thechamber 70. The outer end of the valve member is provided with a knurledknob or the like 84 which extends through an opening 85 in stamping 31in order that it may be manually adjusted from the exterior of thecleaner. A packing ring 86 is preferably providedin order to offersuiicient resistance to turning so that the valve member will not beaccidentally moved as a result of vibrations.

A flexible conduit 88 is connected to the lower chamber 72 and leads toa passage 90 formed in thehose connector 42 and communicating with thepassage 50 therein. Thus it will be seen that the lower surface of thediaphragm 68 is subjected to Athe pressure existing within the passage50, which is the pressure ahead of the bag 56, While the upper surfaceofthe diaphragm is subjected to the pressure existing within the body 10between the bag and the fan, except as this pressure may be modiiied byatmospheric air bled in through the valve 78.

A spring 92 is disposed between the upper surfaceof diaphragm 68 and theupper wall of housing 64. This wall is formed with `a valve port 94which is controlled by means of a valve 96 which is urged towards closedposition by a loading spring 98. The valve is provided with a stem 190which, in the position shown in Fig. 5, is disposed some distance abovethe diaphragm 68.

A passage 102 connects valve port 94`with a chamber 184 in housing 66above a power diaphragm 106. This diaphragm is urged downwardly by acoil spring 188 and carries a'stem 118. SecuredV to the upper end of thestem is a valve member 112 which controls ilow through a port 113leading from the chamber 104 to the' interior of the body 10. A gasket114 is carried by the housing 66 and bears against the bottom of body10. The space below the diaphragm 186 is opened to the atmospherethrough one or more openings 115.

Secured within the body 18 adjacent to the port 113 is a bracket 116 onwhich is pivotally mounted a rocker arm 118 one end of which is disposedabove the stemV 110 of the power diaphragm. The other end of the bearsagainst a pin 120 slidably mounted in the bracket 116, and the lower endof the pin bears against the inner end of a front cover latch 122 whichis pivotally mounted on the wall 28 at 124. The outer end of this arm isformed with a shoulder 128 which is adapted to engage a keeper 130mounted on the front cover 34 so as to retain the cover in closedposition. A spring 132 urges the latch arm 122 towards the positionshown in full lines in Fig. 4.

Arm 118 is secured to a pin 134 on which it is pivotally mounted andthis pin extends to one side of the bracket 116, where it is providedwith a cam 136. This cam bears against a leaf spring 138 secured to thebottom wall Vof housing and carries at its free end a stop 140.

The bottom wall of inner body 22 is formed with an elongated slot 142 inwhich is disposed a cylindrical rail 144,` the frontend of which issecured to the ring 26, while the rear end is secured to the rear wallof the inner body.v Slidably mounted on the rail 144 is an ejectormember 146. A normally flat leaf spring 148 is disposed between the rearwall of the inner body and the ejector member end tends to move thelatter towards the left, as viewed in Fig. 1. Slidably mounted below therail 144 is a latch bar 150 near the rear end of which is secured a leafspring 152. Ejector 146 is formed with a lip 154 which, in the positionof the parts shown in Fig'. l, is engaged by the spring 152. The frontend of the latch bar 158 abuts against the stop 140 so as to retain theejector 146 in its rearward position with the spring 148 compressed. AVbracket 156 carried by the rear wall of the inner body is formed with alower inclined surface 158 so arranged with respect to the spring 152that movement of the latch bar 150 to the left causes the inclinedsurface to cam the free end of the spring 152 downwardly and out ofengagement with the lip 154 of the ejector', thus releasing the latterfor movement by its spring 148.

An electric switch 168 is provided forjcontrolling the supply of currentto the motor 16. This switch may be manually actuated by means of apivoted member 162. In the position shown in Fig. 1, the switch is offand pivoting of the member 162 in a clockwise direction serves to closethe switch. Slidably mounted adjacent the switch is a bar 164 which isurged towards the left, as viewed in Fig. 1, by means of a spring 166.This bar is provided with a projection 168 which is contacted by thefront cover when the latter is closed so as to hold the bar in theposition shown. This bar is provided with an upstanding arm 170 which ispositioned so as to strike a pin 172 extending outwardly from the switchactuating member 162 when the latter is in the on position. Thus, if theswitch is on and the front cover is opened, the bar 164 moves to theleft under the influence of its spring 166 and arm 170 contacts pin `172so as to automatically throw the switch to the off position.

The above described device operates as follows:

With parts in the position shown in Fig. l, that is with a clean dustbag in place within the body and the front cover closed, operation ofthe motor-fan unit serves to draw air in through the inlet 52. This airpasses with but little resistance through the porous material of the bagand through the many openings 24 of the inner body to the inlet of thefan. The pressure existing within the inlet is communicated through theconduit 88 to the chamber 72 below the pressure differential diaphragm68. The pressure existing within the inner body between the bag and theinlet of the fan is communicated to the chamber above the diaphragmthrough the opening 76 and the passage 74. Assuming that the valve 8i)is closed, the diaphragm 68 consequently is subjected to thedifferential of these two pressures, which corresponds to the pressuredrop through the dust bag. When the bag is clean there is but littlepressure drop through it and consequently this differential is verysmall and is not sufficient to displace the diaphragm upwardly againstthe force of the spring 92. However, if dirt is introduced into the bagwith the incoming air, it is retained within the bag and gradually clogsthe pores thereof so as to increase the pressure drop. This of courseincreases the differential acting on the diaphragm 68 and starts toraise the latter by compressing the spring 92. The more this spring iscompressed the greater is the resistance which it offers to furthercompression and the spring is so selected with respect to the area ofdiaphragm 68 that the diaphragm will contact the valve stem when thepressure drop through the bag has attained a Value such that continuedoperation of the cleaner would be inefficient.

When the diaphragm contacts the stem 100 it lifts the valve 96 so as toestablish communication through passage 102 between the high vacuumchamber 70 and the chamber 164 above the large power diaphragm 106. Thiscauses the latter to start moving upwardly against the'force of itsspring 188, which movement opens the valve 112, thus establishing directcommunication through the large port 113 between the chamber 104 and theinterior of the body 10, which causes the diaphragm to quickly move toits upper limit. When the valve 96 opens, air is exhausted from chamber104 through passage 102 into chamber 7i) and hence there is a slightdecrease in the vacuum in the latter chamber which tends to lower thediaphragm 68 and close the valve 96. Also, the pressure drop through thebag uctuates with changes in air ow, and if the air flow were reduced,as by placing the noz'zle on a surface which seals its opening moretightly, just after valve 96 had opened, the resulting reduction inpressure drop might be enough to close the valve. However, even if thevalve 96 is thus closed, this will not interfere with the actuation ofthe power diaphragm 106, inasmuch as initial displacement thereof opensvalve 11.2, and hence high vacuum is thereafter Y applied directly tothe power diaphragm independently of whether or not valve 96 remainsopen.

Upward movement of the power diaphragm causes its stem to pivot the arm118 in a counterclockwise direction, as viewed in Fig. 4. This depressesthe pin which in turn pivots the latch 122 in clockwise direction so asto disengage it from the keeper of the front cover. The spring 38thereupon opens the cover and when this occurs the projection 168 on thebar 164 is released and the spring 166 moves the bar to the left, asseen in Fig. 1, thus moving the switch member 162 Vto its ot posit-ion,which stops the operation of the motor-.fan unit.

Pivoting of the arm 118 causes pin 134 to turn in a counterclockwisedirection, as viewed in Fig. 3, thus causing cam 136 to depress thespring 138, which withdraws Ythe stop from contact with the left end ofthe ejector latch bar 150. As the right-hand end of this bar is coupledto the ejector through engagement of the leaf spring 152 with the lip154, the ejector spring 148 moves both the ejector and the bar 159 tothe left. The inclined surface 158 on the bracket 156 thereupon cams thespring 152 downwardly and out of engagement with the lip 154, whereuponthe ejector is moved all the Way to the left, pushing the bag ahead ofit and out of the cleaner. With the valve 80 fully closed, as wasassumed in the However, if the valve 80 is open so as to bleedatmospheric air into the chamber 70, the vacuum existing in this chamberwill be less than that existing within the body and hence the pressuredifferential acting on the diaphragm will be less than the pressure dropthrough the bag. Consequently, a greater pressure drop through the bagwill be required in order to establish the pressure differentialnecessary to cause the diaphragm 68 to open the valve 96, and the morethe valve 80 is open the greater will be the pressure drop through thebag required to actuate the automatic controls.

While I have shown a more or less speciilc embodiment of my invention itwill be understood that this has been done for purposes of illustrationonly and the scope of my invention is not to be limited thereby, but isto be determined from the appended claims.

What I claim is:

1. In combination with a vacuum cleaner having a casing enclosing a dustseparating member and suction producing means causing iiow of airtherethrough, a power diaphragm, a control diaphragm, means forsubjecting the opposite sides of said control diaphragm to therespective pressures on opposite sides of said dust separating member,valve means operable by a predetermined movement of said controldiaphragm for establishing communication between one side of said powerdiaphragm and said suction producing means, separate valve meansoperated by movement of said power diaphragm for establishingcommunication between said one side of said power diaphragm and saidsuction producing means independently of the tirst mentioned valvemeans, and means operable by said power diaphragm for controlling theoperation of said cleaner.

2. In combination with a vacuum cleaner having a casing enclosing a dustseparating member and suction producing means causing flow of airtherethrough, a power diaphragm, a housing, a control diaphragm dividingsaid housing into two chambers, conduit means for connecting therespective chambers to points in said casing on opposite sides of saiddust separating member, valve means operable by a predetermined movementof said control diaphragm for establishing communication between oneside of said power diaphragm and the chamber adjacent said controldiaphragm which is connected to the point in said casing between saiddust separating member and said suction producing means, separate valvemeans operated by a movement of said power diaphragm for establishingcommunication between said one side of said power diaphragm and saidsuction producing means independently of the rst mentioned valve means,and means operable by said power diaphragm for controlling the operationofV said cleaner.

3. In a vacuum cleaner, a casing capable of maintaining air at lowerthan atmospheric pressure when a suction producing means is operating, adust separating member disposed in said casing, suction producing meanshaving an inlet communicating with a space in said casing adjacent tosaid dust separating member, a control diaphragm, means for subjectingthe opposite sides of i said diaphragm to the respective pressures onopposite sides of said dust separating member, a housing enclosing adiaphragm chamber having an opening communicating directly with saidspace in said casing, a power dlaphrag'm in said chamber, a stemconnected to said power diaphragm and extending through said opening for transmitting motion of said power diaphragm to within said space,valve means operable by a predetermined movement of said controldiaphragm for establishing communication betwen said suction producingmeans and said diaphragm chamber for causing movement of said .powerdiaphragm and stem, separate valve means carried by said stem fornormally closing said opening. and operable by movement of said stem forestablishing communication throughvsaid opening directly between saidspace and said chamber, and means operable by said power diaphragm forcontrolling the operation of said cleaner.

4. In a vacuum cleaner, a casing capable of maintain- Y ing air at lowerthanatmospheric pressure while a suction producing means is operating, adustV separating member disposed in a space in said casing,'suctionproducing means having an inlet communicating with said space, a firsthousing, a control diaphragm dividing said housing into a high suctionchamber and a low suction chamber, means for connecting said highsuction chamber with said space and for connecting said low suctionchamber with a region of said casing which is separated from said spaceby said dust separating member, a,second housing enclosing a diaphragmchamber having an opening communicating directly with said space, apower diaphragm forming a wall of said diaphragm chamber, a stemconnected to said power diaphragm and extending through said opening fortransmitting motion of said power diaphragm to within said space, valvemeans in said first housing operably by a predetermined movement of saidcontrol diaphragm for establishing communication between said highsuction chamber and said diaphragm chamber for causing movement of saidpower diaphragm and stem, separate valve means carried by said stem fornormally closing said opening and operable by movement of said stem forestablishing communication through said opening directly between saidspace and said diaphragm chamber, and means operable by said powerdiaphragm for controlling the operation of said cleaner.

5. In a vacuum cleaner, a casing capable of maintaining air at lowerthan atmospheric pressure while a suction producing means is operating,a dust bag disposed in a space in said casing, ejector mechanismdisposed in said space and releasable for ejecting said bag from saidcasing, suction producing means having an inlet communicating with saidspace, a control diaphragm, means for subjecting the opposite sides ofsaid diaphragm to the respective pressures on opposite sides of saiddust bag, a housing enclosing a diaphragm chamber having an openingcommunicating directly with said space, a power diaphragm in saidchamber, a stem connected to said power diaphragm and extending throughsaid opening and movable by said power diaphragm for releasing saidejector mechanism, valve means operable-by movement of said controldiaphragm for establishing communication between said suction producingmeans and said diaphragm chamber for causing movement of said powerdiaphragm and stem, and separate valve means carried by said stem fornormally closing said opening and operable by movement of said stem forestablishing communication through said opening directly between saidspace and said diaphragm chamber.

6. In a vacuum cleaner, a casing capable of maintaining air at lowerthan atmospheric pressure while a suction producing means is operating,a dust bag disposed in'a space in said casing, ejector mechanismdisposed in said space and releasable for ejecting said bag from saidcasing, suction producing means having an inlet communicating with saidspace, a rst housing, a control diaphragm dividing said housing into ahigh suction chamber and a low suction chamber, means for connectingsaid high suction chamber with said space and for connecting said lowsuction chamber with a region of said casing which is separated fromsaid space by said dust bag, a second housing enclosing a diaphragmchamber having an opening communicating directly with said space, apower diaphragm associated with said diaphragm chamber, a stem connectedto said power diaphragm and extending through said opening and movableby said power diaphragm for releasing said ejector mechanism, valvemeans in said first housing operable by a predetermined 7 movement ofsaid control diaphragm forestabli'shing communication between said highsuction chamber and said diaphragm chamber for causing movement of Saidpower diaphragm and stem, and separate valve means car- A ried by saidstem for normally closing said opening and operable by movement of saidstem for establishing communication through said opening directlybetween said space and said diaphragm chamber.

References Cited in the file of thisl patent UNITED STATES PATENTSThomsona. V Feb. 23, 1944

